(HAMMOND) - Two children are out of the hospital after being injured in a northwestern Indiana house fire that killed three siblings and critically injured their father.

A Cook County hospitals system spokeswoman tells The Times of Munster that the 2-year-old and 6-year-old boys were released Saturday from Stroger Hospital in Chicago.

Fire investigators believe a propane-fueled space heater started the fire Wednesday night at the Hammond house. Authorities say 7-month-old Jayden Young, 4-year-old Dasani Young and 3-year-old Alexia Young died from burns.

Stephanie Pittman tells the Post-Tribune her surviving grandchildren are in foster care and that she plans to ask a judge to award her custody.